This invention relates to household refrigerators and in particular to the cabinet assembly for a refrigerator having a freezer compartment on top, a fresh food compartment on the bottom, and incorporating an anti-sweat heater.
It is common practice in the manufacture of household refrigerators to incorporate an anti-sweat heater in the front face of the freezer compartment which surrounds the access opening of that compartment and these heaters are either electric resistance heaters or hot liquid loop heaters. The refrigeration system of a household refrigerator includes a compressor, condenser and evaporator wherein refrigerant compressed by the compressor is pumped to the condenser. The condenser cools the gas to form a liquid which subsequently passes through a capillary tube to the evaporator where heat from inside the refrigerator is used to evaporate the liquid in the evaporator and the resultant gas is then returned to the compressor by the suction line. The condenser is an elongated tube that is formed in a serpentine and contains hot refrigerant liquid and a portion of the tube or loop may be used to perform the anti-sweat function in the refrigerator.
It is normal for refrigerators and particularly the freezer compartment of the refrigerators to have some small amount of cold air leakage and/or normal conduction through the gasket sealing the access door to the freezer compartment and that small amount of leakage can cause the front face to be cold. Condensation results around the face of the freezer compartment when warm humid room ambient air comes in contact with the cold surface. The anti-sweat heater is to warm the area around the front face of the freezer compartment so that condensation is minimized.
It has been the usual practice in installing the hot liquid loop in a refrigerator cabinet that it be secured in some manner usually by many metal or plastic clips. The manipulation of the rather long, small diameter tube forming the loop to place it correctly in the cabinet for good heat transfer characteristics is very difficult. This practice results in costly installation and due to the tolerances involved the liquid loop may not be retained tightly against the front face of the freezer compartment for maximum heat transfer.
U.S. Pat. No. 4,735,062 assigned to the same assignee as the present invention describes a cabinet assembly for a refrigerator wherein the hot liquid anti-sweat loop may be assembled with a minimum amount of metal or plastic clips to hold the loop tightly against the corner of the cabinet for maximum heat transfer. This invention relates to such an assembly and a specific clip structure that may be utilized in a minimum amount to assure that the liquid loop is retained tightly against the corner of the refrigerator cabinet for maximum heat transfer.
Another approach which is widely practiced to prevent sweating of the cabinet is the use of electric resistance heaters disposed within the refrigerator cabinet which may be turned on and off as needed to prevent the condensate formation. U.S. Pat. No. 4,474,017 assigned to the same assignee as the present invention describes a method of assembling an anti-sweat heater of the electric resistance type in a refrigerator cabinet. While an electric resistance heating element is relatively simple to incorporate and readily controllable by a manual control switch, electric resistance heating increases the power required to operate the refrigerator. If the heater is not properly located and therefore not in good heat transfer relationship with the cabinet outer surfaces, it is not as effective to prevent condensate on the cabinet. The clip of the present invention may be used to properly locate the electric resistance heater in the corner of the cabinet to effect good heat transfer relationship the same as with the hot liquid loop.
By this invention there is provided a method whereby an anti-sweat heater is secured to a refrigerator cabinet and in good heat transfer relationship.